Core-shell NiFe2O4@TiO2 nanorods: an anode material with enhanced electrochemical performance for lithium-ion batteries.

Hierarchical porous core-shell NiFe2O4@TiO2 nanorods have been fabricated with the help of hydrothermal synthesis, chemical bath deposition, and a subsequent calcinating process. The nanorods with an average diameter of 48 nm and length of about 300-600 nm turn out have a highly uniform morphology and are composed of nanosized primary particles. Owing to the synergistic effect of individual constituents as well as the hierarchical porous structure, the novel core-shell NiFe2O4@TiO2 nanorods exhibit superior electrochemical performance when evaluated as anode materials for lithium-ion batteries. At the current density of 100 mA g(-1), the composite exhibits a reversible specific capacity of 1034 mAh g(-1) up to 100 charge-discharge cycles, which is much higher than the uncoated NiFe2O4 nanorods. Even when cycled at 2000 mA g(-1), the discharge capacity could still be maintained at 358 mAh g(-1).